1. Field of the Invention
The present invention relates to a video printer and particularly to a video printer in which a video signal is processed to produce a hard copy as a visible image.
2. Description of the Prior Art
Conventionally, a visible image recording apparatus commonly known as a video printer has been of a large size in many cases. For example, in accordance with the Japanese Patent Laid-Open Publication No. 16695/1987 filed by the applicant of the present invention, an image recording apparatus receives a video signal of an image shot by an electronic still camera so as to produce the image on a CRT, thereby recording the image on a sheet of color photographic paper. The apparatus is primarily suitable for professional uses to create a color hard copy with a high resolution. However, this device necessitates an optical system for generating a focused image of the CRT image on the photographic paper, which increases the size of the apparatus and requires a long period of time for the image recording operation. Therefore, the apparatus is expensive.
As an image recording apparatus similarly employs a CRT, an instant-type equipment has been known. In this system, an exposure of an instant photosensitive material is conducted by use of an image displayed on a CRT. The apparatus includes a focusing optical system adopting an optical fiber or a lens. According to this method, the system configuration is simple and the print time is short; however, due to necessity of the focusing optical system, the apparatus size is increased.
Furthermore, as described in the Japanese Patent Publication No. 10991/1989 (Japanese Patent Laid-Open No. 212287/1983), for example, a thermal printer for producing a hard copy of an image by transcribing a dye having a thermal diffusion characteristic onto an image receiving medium has been proposed. This apparatus adopts a thermal head in which heating elements are arranged in a line and does not require any optical system. In consequence, although the system size is relatively minimized, the system cannot be conveyed in a pocket, for example. Although the price of the apparatus is relatively low, a long period of print time is necessary. A general tendency of electronic apparatus is also recognized in the field of video printers. That is, a small-sized video printer in which a hard copy of a visible image is easily produced from a usual video signal has been desired.